What if every city had a London Overground?

Summary

An underground train network is the pinnacle of public transport—right now, in New York and Chicago, Paris and Berlin, Tokyo and Beijing, people are being whisked through a network of tunnels, deep below the bustling city. In London, which has the oldest rapid transit system in the world, the Tube isn’t just public transportation—it’s famous as the beating heart of the city, assisting up to five million passenger journeys a day. Formally known as the London Underground, the Tube’s logo is soon recognized by everyone who visits—the red circle and blue bar roundel is a symbol for the city itself. But for many Londoners these days, it’s not the red Underground symbol that sparks the most joy—it’s an orange one, because that means you’re on the Overground. In one of the busiest cities in the world, the Overground is a train network that actually lowers your blood pressure. Like the Tube, it’s a property of the city-run Transport for London (TfL) transit operator, but the Overground is a different experience altogether: it’s spacious, airy and quiet as it moves through daylight. In contrast, the oldest parts of the Tube are more than a hundred years old, with tight tunnels dug long before anyone thought to leave space to add air-conditioning to snug carriages. Upgrades are on the way but it’s slow going, and the deeper lines are still roasting hot in summer. Parts of the Tube are as loud as a music concert with air quality that’s genuinely terrible, and at rush hour you will definitely find yourself nose-to-armpit with a fellow traveler, questioning your love of city life. If the Tube is a starburst, crossing the center of London to move people out in every direction, then the Overground is a spiral, providing an outer ring for travel without having to enter the hectic middle. Less than half the size of the Tube by every metric, the Overground spans 104 miles and 113 stations, divided into six lines. Last year, 183 million passengers traveled on the Overground, averaging...